An Earthquake in Design
An Earthquake in Design
In Japan, the Diet had mixed feelings about Washington. It cemented Japan's place at the table; but it was next to the great powers, not necessarily as one of them. The limit of 465,000 tons preserved some of the best of the new ships already under construction, while the ‘8-8’ program was already known to be ruinously expensive. The two ‘Tosa’ class battleships were completed in 1922, but a modest slowdown in pace and rate of expenditure meant that Amagi and Akagi did not enter service until 1923.
Completion of these four would take the IJN up to 462,000 tons.
With the ships still under construction, the Japanese Naval Staff decided to wait and see what Britain and America laid down, believing that their designers could come up with something better.
By late 1922, they had done, and in December that year the battleships Kii and Owari were laid down. As required by treaty, the other powers were informed that the ships were 795’ long, with 101’ beam and would have a draught of 27’ at a Standard Displacement of 36,000 tons.
Such dimensions provoked some suspicion; they were only 31’ shorter than the 41,500-ton ‘Amagis’, although draught was quoted as being less.
Both British and American designers suspected that the Amagis were over their quoted weights. In fact, Amagi herself had come out at 42,250 tons, but the Japanese were not obliged to inform anyone of this, as the figure of 41,500 tons was written into the Treaty as ‘normal’ displacement.
In 1922, the Japanese had no intention of breaking the Treaty, but had noted that contracting powers were obliged to declare the design displacement when the ships were laid down, and the actual displacement once they were completed. They therefore intended to avoid overtly breaking the 36,000-ton ‘implied maximum’, but if the new ships completed a little heavy, it could always be declared later.
As it turned out, that declaration would come much later. On the 1st September 1923, a severe earthquake struck Tokyo and its surroundings, damaging the hull of the Kii, which lay on a slip at Yokosuka Naval Yard. The quake was a dramatic setback for the entire country, and certainly delayed her naval programme by six months, perhaps as much as a year in some cases. The incomplete hull was scrapped on the slip, and some of the material was later re-used in the construction of a new Kii, which was laid down in February 1924.
The ‘Kii’ class took the machinery and hull of ‘Amagi’ and compacted them slightly by eliminating the mixed-firing arrangements. Three triple 16” turrets would mount the same gun as on earlier ships.
A compact arrangement of the boilers and magazines allowed the main belt to be just 377’ long, with one of the engine rooms situated behind the aft turret, protected by a shallower belt that also ran forwards, totalling 133’ in length. All the belt armour was 300mm thick (usually listed as 12”) and inclined at 12-degrees with the side of the hull. The armour deck moved down a level with the drop in the belt, and was a total of 100mm (3.9”) thick. This was split between an 80mm deck at the top of the belt and a 20mm splinter deck below, except over the engine rooms, where the two came together. Barbettes were 13” thick and there was a 14” conning tower, but the turrets were little better protected than those of ‘Nagato’, with 13” faces and 5” roofs. Battery armour was 6”, with a 2” splinter deck beneath it.
On completion, the ships proved to be over the intended 36,000 tons, and once further reinforcing had been added around the bow and the areas where the side armour stepped down, the ships were about 37,300 tons Standard, and it was this weight than the Japanese declared in 1927 once Kii had been completed. They certainly used the ‘trick’ of declaring part-filled magazines, and the ships’ Full Load was 43,790 tons at the time of completion. Addition of 100mm and 12.7mm anti-aircraft guns (as permitted by the ‘3000-ton rule’) soon added to this figure, and the ships were undoubtedly over 45,000 tons Full Load within a few years of their completion.
That weight and size brought with it considerable speed. On trials in 1926, Owari achieved 30.88 knots with 139,200shp, while at 40,470 tons. In service, they were usually regarded as good for 29 knots, and were quite capable of keeping up with the ‘Amagis’.
Owari as completed
Four ‘Myoko’ class cruisers were also authorised at the same time as the 'Kii' class, but again the earthquake intervened. The hull of the Myoko had been completed up to the lower deck when the quake struck, damaging the slip itself and twisting the hull. She was re-laid the following year, while the others were delayed due to the national crisis, finally completing in 1927.
Nominally a 10,000-ton design when they were laid down, the Japanese were not obliged to inform their Treaty partners of the new class. However, during construction their weight grew considerably, and they completed at close to 11,500 tons once strengthening beams had been added to the overloaded hulls.
However, Japan was still bound by the Treaty, which stated that the other powers should be informed of the laying-down or the completion of cruisers over 10,000 tons. They therefore informed their fellow signatories that the four ships had completed at 10,750 tons; itself a lie, but sufficiently close to the truth to avoid any future problems.
Meanwhile, both France and Italy were in poor financial shape. Despite French bellicosity at Washington, there was no question of France using her 210,000-ton limit at any time in the next few years. The four battleships of the Courbet class and the three Bretagnes would lead the French Navy for the foreseeable future. Italy was keeping a wary eye to both the East and West, but with a recovery only just established following a post-war boom then slump, there were no plans for any new heavy ships in 1922. Both nations, however, were urgently looking at the possibilities offered by modern cruisers.
In Japan, the Diet had mixed feelings about Washington. It cemented Japan's place at the table; but it was next to the great powers, not necessarily as one of them. The limit of 465,000 tons preserved some of the best of the new ships already under construction, while the ‘8-8’ program was already known to be ruinously expensive. The two ‘Tosa’ class battleships were completed in 1922, but a modest slowdown in pace and rate of expenditure meant that Amagi and Akagi did not enter service until 1923.
Completion of these four would take the IJN up to 462,000 tons.
With the ships still under construction, the Japanese Naval Staff decided to wait and see what Britain and America laid down, believing that their designers could come up with something better.
By late 1922, they had done, and in December that year the battleships Kii and Owari were laid down. As required by treaty, the other powers were informed that the ships were 795’ long, with 101’ beam and would have a draught of 27’ at a Standard Displacement of 36,000 tons.
Such dimensions provoked some suspicion; they were only 31’ shorter than the 41,500-ton ‘Amagis’, although draught was quoted as being less.
Both British and American designers suspected that the Amagis were over their quoted weights. In fact, Amagi herself had come out at 42,250 tons, but the Japanese were not obliged to inform anyone of this, as the figure of 41,500 tons was written into the Treaty as ‘normal’ displacement.
In 1922, the Japanese had no intention of breaking the Treaty, but had noted that contracting powers were obliged to declare the design displacement when the ships were laid down, and the actual displacement once they were completed. They therefore intended to avoid overtly breaking the 36,000-ton ‘implied maximum’, but if the new ships completed a little heavy, it could always be declared later.
As it turned out, that declaration would come much later. On the 1st September 1923, a severe earthquake struck Tokyo and its surroundings, damaging the hull of the Kii, which lay on a slip at Yokosuka Naval Yard. The quake was a dramatic setback for the entire country, and certainly delayed her naval programme by six months, perhaps as much as a year in some cases. The incomplete hull was scrapped on the slip, and some of the material was later re-used in the construction of a new Kii, which was laid down in February 1924.
The ‘Kii’ class took the machinery and hull of ‘Amagi’ and compacted them slightly by eliminating the mixed-firing arrangements. Three triple 16” turrets would mount the same gun as on earlier ships.
A compact arrangement of the boilers and magazines allowed the main belt to be just 377’ long, with one of the engine rooms situated behind the aft turret, protected by a shallower belt that also ran forwards, totalling 133’ in length. All the belt armour was 300mm thick (usually listed as 12”) and inclined at 12-degrees with the side of the hull. The armour deck moved down a level with the drop in the belt, and was a total of 100mm (3.9”) thick. This was split between an 80mm deck at the top of the belt and a 20mm splinter deck below, except over the engine rooms, where the two came together. Barbettes were 13” thick and there was a 14” conning tower, but the turrets were little better protected than those of ‘Nagato’, with 13” faces and 5” roofs. Battery armour was 6”, with a 2” splinter deck beneath it.
On completion, the ships proved to be over the intended 36,000 tons, and once further reinforcing had been added around the bow and the areas where the side armour stepped down, the ships were about 37,300 tons Standard, and it was this weight than the Japanese declared in 1927 once Kii had been completed. They certainly used the ‘trick’ of declaring part-filled magazines, and the ships’ Full Load was 43,790 tons at the time of completion. Addition of 100mm and 12.7mm anti-aircraft guns (as permitted by the ‘3000-ton rule’) soon added to this figure, and the ships were undoubtedly over 45,000 tons Full Load within a few years of their completion.
That weight and size brought with it considerable speed. On trials in 1926, Owari achieved 30.88 knots with 139,200shp, while at 40,470 tons. In service, they were usually regarded as good for 29 knots, and were quite capable of keeping up with the ‘Amagis’.
Owari as completed
Four ‘Myoko’ class cruisers were also authorised at the same time as the 'Kii' class, but again the earthquake intervened. The hull of the Myoko had been completed up to the lower deck when the quake struck, damaging the slip itself and twisting the hull. She was re-laid the following year, while the others were delayed due to the national crisis, finally completing in 1927.
Nominally a 10,000-ton design when they were laid down, the Japanese were not obliged to inform their Treaty partners of the new class. However, during construction their weight grew considerably, and they completed at close to 11,500 tons once strengthening beams had been added to the overloaded hulls.
However, Japan was still bound by the Treaty, which stated that the other powers should be informed of the laying-down or the completion of cruisers over 10,000 tons. They therefore informed their fellow signatories that the four ships had completed at 10,750 tons; itself a lie, but sufficiently close to the truth to avoid any future problems.
Meanwhile, both France and Italy were in poor financial shape. Despite French bellicosity at Washington, there was no question of France using her 210,000-ton limit at any time in the next few years. The four battleships of the Courbet class and the three Bretagnes would lead the French Navy for the foreseeable future. Italy was keeping a wary eye to both the East and West, but with a recovery only just established following a post-war boom then slump, there were no plans for any new heavy ships in 1922. Both nations, however, were urgently looking at the possibilities offered by modern cruisers.
